Golf club head with stiffening and sound tuning composite member

ABSTRACT

A golf club head with sound tuning composite members forming at least a portion of the golf club head is disclosed herein. The composite members being a composite layer made out of a sandwiched core layer that is interposed inside the midsection of the composite member to provide strength, vibration-damping, and/or sound-tuning characteristics.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/739,325, filed Jan. 11, 2013, which is a continuation ofU.S. patent application Ser. No. 13/192,346, filed Jul. 27, 2011, nowU.S. Pat. No. 8,353,783, which is a continuation of U.S. patentapplication Ser. No. 12/334,563 filed Dec. 15, 2008, now U.S. Pat. No.8,007,369. All of the above applications are incorporated herein byreference in their entireties.

FIELD OF THE INVENTION

The present invention relates to a golf club head with at least onecomposite member forming at least a portion of an outer surface of thegolf club head, and more specifically a golf club head where thecomposite members is multi-layered with a sandwiched core layerinterposed inside the composite member to provide one or more of thefollowing: structural stiffness, vibration damping, and sound tuning forthe golf club head.

BACKGROUND OF THE INVENTION

The complexities of golf club design are known. The specifications foreach component of the club (i.e., the club head, shaft, grip, andsubcomponents thereof) directly impact the performance of the club.Thus, by varying design specifications, a golf club can be tailored tohave specific performance characteristics.

The design of club heads has long been studied. Among the more prominentconsiderations in club head design are loft, lie, face angle, horizontalface bulge, vertical face roll, center of gravity, rotational moment ofinertia, material selection, overall head size, and overall head weight.While this basic set of criteria is generally the focus of golf clubdesigners, other design aspects unrelated to performance such as soundof the club head upon impact with a ball must also be considered.

As the size of golf club heads has increased, weight distribution hasbecome a major design consideration. In particular, in the quest todesign in additional discretionary mass, it has become desirable todecrease the wall thicknesses of the portions of the club head wall thatdo not improve mass properties. Additionally, composite materials havealso been used in the past to replace various sections of the club headwalls to further improve weight distribution and generate discretionarymass. Because of the thin walls, composite materials, and the largevolumes of the golf club head; large portions of the heads act asmembranes and vibrate relative to each other. In some instances, thevibration that takes place could result in an unappealing sound duringimpact between the golf club and the golf ball.

Golfers have become accustomed to hearing a particular sound when thegolf club impacts the golf ball, especially when a large volume golfclub is used. This “ideal sound”, although often a result of personalpreference, can drastically turn into an unappealing sound if it variestoo much from the above mentioned “ideal sound.”

Various sound tuning features have been incorporated into hollow bodiedgolf clubs to try and capture and maintain this “ideal sound”. Oneexample is described in U.S. Pat. No. 6,852,038 to Yabu for a Golf ClubHead and Method of Making the Same. In that example, a hollow body golfclub head includes rib-like walls that form the inner surface of thesole and crown. The sound emitted into the hollow cavity due to contactwith a golf ball is directed rearward and parted laterally by the ribs.Sound bars are included in some embodiments that are located a smalldistance behind the club face and extends between the crown and sole.The sound bars are included to further part the sound vibrations.

Another example is described in U.S. Pat. No. 5,718,641 to Lin for aGolf Club head that Makes a Sound when Striking the Ball. In thatexample, the golf club head includes a sound plate that is suspended inthe hollow body of the club head that makes a sound and echoes the soundduring impact between the club head and a golf ball. One edge of thesound plate is fixed to a wall of the hollow club head and the remainingedges are unattached so that the sound plate is able to vibrate to theremainder of the club head.

As an alternative to adding sound ribs or ridges, others have addedfeatures to golf club heads to improve rigidity of the club head byreducing relative vibration between opposing walls to reduce the energythat is waste din deforming the club head and to redirect that energyinto the golf ball. For example, U.S. Pat. No. 6,524,197 to Boone for aGolf Club Head Having a Device for Resisting Expansion Between OpposingWalls During Ball Impact describes a feature designed for the abovestated purpose. The golf club head includes a tensioning device thatextends between the crown and sole. In particular, the tensioning deviceincludes an elongated cylindrical member that extends through aperturesin each of the crown and sole and enlarged ends that are unable to passthrough the apertures. One of the enlarged heads is threaded so that athreaded end member may be used to tension the elongate cylindricalmember thereby placing the hollow body in compression and increasing therigidity of the hollow body.

It can be seen from above that despite numerous attempts to control thesound, the current art utilize heavy and burdensome objects such asribs, ridges, panels, or even posts within the internal cavity of thegolf club head to create structural stiffness, control vibrationdamping, and adjust the sound. The additions of these heavy andburdensome objects are undesirable not only because they are expensiveto manufacture, but they could also add additional weight to the golfclub head at locations that may not be desirable for performanceoptimization.

Hence, it can be seen that there is a need in the field for a golf clubhead that is capable of controlling the sound characteristics withoutheavy and burdensome objects inserted into the internal cavity of thegolf club head. More specifically, there is a need for a golf club headthat utilizes the pre-existing performance optimization components suchas a composite member, and modifying the internal composition of thecomposite member to provide structural stiffness, vibration damping, andsound tuning characteristics.

BRIEF SUMMARY OF THE INVENTION

In one aspect of the present invention, a golf club head comprising of ahitting face providing a surface area for striking a golf ball, a bodysection including a crown section and a sole section and extending froma rear section of the hitting face, and a composite member forming atleast a portion of the surface of the golf club head; wherein thecomposite member further comprises of a sandwiching outer layer, asandwiching inner layer, and a sandwiched core layer interposed betweenthe sandwiching outer layer and the sandwiching inner layer; wherein thesandwiched core layer is of a different material composition than thesandwiching outer layer and the sandwiching inner layer. The sandwichedcore layer may comprise many different lightweight materials, such asfoam, resin-impregnated paper, or balsa wood. The sandwiched core layermay be configured in a high-strength pattern, such as a honeycomb ordistributed cellular pattern.

In another aspect of the present invention, a golf club head comprisingof a hitting face providing a surface area for striking a ball, a bodysection including a crown section and a sole section and extending froma rear section of the hitting face, and a composite member forming atleast a portion of the surface of the golf club head; wherein thecomposite member further comprises of a sandwiching outer layer, asandwiching inner layer, and a sandwiched core layer comprising of avibration damping material interposed between the sandwiching outerlayer and the sandwiching inner layer; wherein said golf club head has avolume ranging from 350 cubic centimeters to 495 cubic centimeters; andwherein said golf club head has a length ranging from 3.5 inches to 5.0inches and a width ranging from 4.0 inches to 5.0 inches.

In another aspect of the present invention, a method of altering soundof a golf club head comprising of connecting a body section to the rearsection of the golf club head, replacing at least a portion of thesurface of the body section with a composite member; wherein thecomposite member is comprising of a sandwiching outer layer at anexternal surface of the golf club head, and a sandwiching inner layer atan internal surface of the golf club head, interposing a vibrationdamping material between the sandwiching outer layer and the sandwichinginner layer.

These and other features, aspects and advantages of the presentinvention will become better understood with references to the followingdrawings, description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and advantages of the invention will beapparent from the following description of the invention as illustratedin the accompanying drawings. The accompanying drawings, which areincorporated herein and form a part of the specification, further serveto explain the principles of the invention and to enable a personskilled in the pertinent art to make and use the invention.

FIG. 1 shows a side profile view of one embodiment of the presentinvention wherein the composite member is located at the crown;

FIG. 2 shows a top view of the embodiment of the present invention asshown in FIG. 1;

FIG. 3 shows a cross-sectional view of the embodiment of the presentinvention as shown in FIG. 2 taken along line A-A;

FIG. 4 shows an alternative embodiment of the present invention whereinthe composite member is located at the sole;

FIG. 5 shows a cross-sectional view of an alternative embodiment of thepresent invention as shown in FIG. 4, taken along the midsection similarto line A-A;

FIG. 6 shows a cross-sectional view of a further alternative embodimentof the present invention taken along the midsection similar to lineA-A′, wherein the composite member has a different profile;

FIG. 7 shows a cross-sectional view of a further alternative embodimentof the present invention taken along the midsection similar to lineA-A′, wherein the composite member has a different profile;

FIG. 8 shows a top view of a further alternative embodiment of thepresent invention, wherein the composite member has a different profile;

FIG. 9 shows a top view of a further alternative embodiment of thepresent invention wherein the composite member has a different profile;

FIG. 10 shows a top view of a further alternative embodiment of thepresent invention wherein the composite member has a different profile;

FIG. 11 shows a top view of a further alternative embodiment of thepresent invention wherein the composite member has a different profile;

FIG. 12 shows a cross-sectional side view of a further alternativeembodiment of the present invention taken along A-A′ as shown in FIG.11;

FIG. 13 shows a top profile view of an embodiment of the inventionwherein a sandwiched core layer comprises voids in a honeycomb pattern;

FIG. 14 shows a cut-away view of the embodiment shown in FIG. 13 takenalong B-B′;

FIG. 15 shows a top profile view of an embodiment of the inventionwherein a sandwiched core layer comprises voids in a cellular pattern;and

FIG. 16 shows a cut-away view of the embodiment shown in FIG. 15 takenalong C-C′.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is of the best currently contemplatedmodes of carrying out the invention. The description is not to be takenin a limiting sense, but is made merely for the purpose of illustratingthe general principles of the invention, since the scope of theinvention is best defined by the appended claims.

Various inventive features are described below and can each be usedindependently of one another or in combination with other features.However, any single inventive feature may not address any or all of theproblems discussed above or may only address one of the problemsdiscussed above. Further, one or more of the problems discussed abovemay not be fully addressed by any of the features described below.

The present invention generally provides a golf club head withstiffening and sound tuning capabilities and characteristics. Morespecifically, the present invention utilizes a golf club head that iscomprised of two or more materials and utilizing an already existentcomposite member that forms at least a portion of the surface of thegolf club head to provide stiffening and sound tuning characteristics.Even more specifically, the current invention may include a sandwichedcore layer interposed in the middle between multilayer composite membersthat form the composite member to directly provide stiffness within thegolf club head. Sound characteristics may be dramatically improvedthrough a combination of engineered dampening systems and a tailoredvariation in structural stiffness. The current invention is unlike theprior art golf club heads wherein heavy, burdensome, expensive, andcomplicated components are installed within the internal cavity of thegolf club head to provide stiffness to address the vibration and soundissue. The current invention utilizes pre-existing composite memberswithin a golf club head that was traditionally used for weight savingpurposes, and adds an additional stiffening and vibration damping layerdirectly within the composite member to improve sound tuningcharacteristics.

Every golf club produces a distinct sound and feels when it is used tostrike a golf ball. The sound and feel which are produced by thevibration behavior of the golf club head, may often be a result of thedesign of the golf club head. Golf club head designs may be analyzed andsamples may be tested to characterize the vibration characteristics of aparticular design in an attempt to determine whether the sound and feelproduced by a golf club head will be acceptable to the average golfer.In particular, the frequency values and displacement mode shapes aredetermined for the club head. It is generally understood that lowerfrequency modes have a tendency to detrimentally affect the sounds andfeel of a particular golf club head.

FIG. 1 shows a side view of one embodiment of the present inventionshowing golf club head 100 which may contain a hitting face 102 at afore section of golf club head 100 wherein a surface area is providedfor striking a ball. In this current exemplary embodiment, golf clubhead 100 may contain a face insert 103 to further provide an area forstriking the ball; however, hitting face 102 may also can be a unitarycomponent without departing from the scope of the present invention.Connected to the rear section of hitting face 102 is a body section 104which may comprise of a crown section 106, a sole section 108, and askirt section 109. It should be noted that in an alternative embodiment,skirt section 109 could often be classified as part of the crown section106 or part of the sole section 108 all without departing from the scopeof the present invention. Here, as shown in FIG. 1 of the currentexemplary embodiment, golf club head 100 may have a composite member 110connected to a crown section 106 of the body section 104 to providestiffening and vibration damping to golf club head 100.

FIG. 1 also shows that in the current exemplary embodiment, thecomposite member 110 may generally be made out of a different materialthan the remainder of the body section 104 of the golf club head 100.“Composite member” 110 as described in this current exemplary embodimentmay generally be made out of a composite material that is different thanthe remainder of the body section 104. This composite member may offerweight saving capabilities by changing the material to differentmaterials that provides weight saving capabilities all within the scopeof the present invention.

Golf club head 100, here in this current exemplary embodiment, may havea preferable volume range of approximately 300 cubic centimeters toapproximately 600 cubic centimeters, and more preferably in the volumerange of approximately 350 cubic centimeters to approximately 550 cubiccentimeters, even more preferably in the volume range of approximately375 cubic centimeters to approximately 475 cubic centimeters, and mostpreferably approximately 420 cubic centimeters to approximately 460cubic centimeters; all without departing from the scope of the presentinvention.

The mass of golf club head 100 of the present invention ranges from 165grams to 250 grams, preferably ranges from 175 grams to 230 grams, andmore preferably from 190 grams to 210 grams. More specifically, faceinsert 103, as shown in the present exemplary embodiment may have aweight of approximately 20 grams to approximately 60 grams, preferablyranging from approximately 30 grams to approximately 50 grams, and morepreferably from approximately 35 grams to approximately 45 grams.Additionally, the body section 104, as shown in the present exemplaryembodiment may have a weight of approximately 115 grams to approximately145 grams, preferably ranging from approximately 120 grams toapproximately 140 grams, and more preferably from approximately 125grams to approximately 135 grams.

Golf club head 100 in this current exemplary embodiment may have apreferred length range of approximately 3.5 inches to 5.0 inchesmeasuring from the face of the club towards the skirt of the club inaccordance with USGA definitions; more preferably 4.0 inches to 5.0inches, and most preferably 4.5 inches to 5.0 inches. Additionally golfclub head 100 may have a preferred width range of approximately 4.0inches to 5.0 inches measuring from the widest part of the heel to thewidest part of the sole in accordance with USGA definitions; morepreferably 4.5 inches to 5.0 inches.

Hitting face 102 in this current exemplary embodiment is generally madeout of a metallic material, and generally placed at the fore section ofgolf club head 100 for contact with a golf ball. Hitting face 102 maygenerally be made out of titanium alloy materials for their performancecharacteristics when in contact with a golf ball, however numerous othermaterials other than titanium alloy may also be used without departingfrom the scope of the present invention. The face insert 103 maygenerally have the same consistent material as the remainder of hittingface 102; however, face insert 103 may be made out of a differentmaterial such as a heat treated 6-20-20 titanium alloy or any othermaterial capable of providing a serviceable striking area withoutdeparting from the scope of the present invention.

FIG. 2 shows a top view of golf club head 200 in accordance with anembodiment of the present invention. The top view of golf club head 200,as shown in the current exemplary embodiment, shows the composite member210 covering the majority of the crown section 206. This arrangement ofthe composite member 210 allows for increased weight shifting from thecrown section 206 and creates the increased amount of discretionaryweight. However, nonmetallic member 210 may only be a minor part of thecrown section 206 without departing from the scope of the presentinvention.

Turning now to FIG. 3 showing a cross-sectional view of the exemplaryembodiment of the present invention taken along the middle of golf clubhead 200 as depicted by line A-A′ in FIG. 2. The cross-sectional view ofthe current exemplary embodiment shows that the composite member 310 maybe further comprised of a sandwiching outer layer 312 at a top outersurface of the composite member 310, a sandwiching inner layer 314 at abottom inner surface of the composite member 310, and a sandwiched corelayer 316 interposed between the sandwiching outer layer 312 and thesandwiching inner layer 314. The sandwiched core layer 316, as shown inthe current exemplary embodiment may further provide structural rigidityto composite member 310, which in turn may also provide vibrationdamping to improve sound.

Body section 304 in this current exemplary embodiment may generally becomprised of a crown section 306 and a sole section 308. In alternativeembodiments, body section 304 could contain various other componentssuch as a skirt section, a toe section, a heel section, or any othersection not defined as a hitting face 302 all without departing from thescope of the present invention. The crown section 306 and sole section308 form the upper and lower surfaces, respectively, of body section304. Additionally, body section 304 generally provides the majority ofthe surface area of golf club head 300. In order to maintain the largevolume of modern golf club heads while providing maximum discretionarymass, crown section 306 and sole section 308 tend to have relativelythin walls, which results in those portions often acting as a vibratingmembrane during and after impact with the golf ball. Crown section 306and sole section 308 may be spaced apart from each other, and theycombine to form the body section 304 with or without any furthersubcomponents such as a skirt section, a toe section, and a heelsection; all without departing from the scope of the present invention.

The cross-sectional view of golf club head 300 allows the variablethickness feature of face insert 303 to be shown. Here, hitting face 302may contain a variable face thickness section 305 within the face insert303 as shown by U.S. Pat. Pub. 2006/0068932 the disclosure of which isincorporated by reference in its entirety; however, hitting face 302could also be of a uniform thickness or even without a face insert allwithout departing from the scope of the present invention.

Body section 304 in this current exemplary embodiment may generallyconsist of a metallic member of the golf club head 300 and a compositemember 310 of golf club head 300 that is of a different material thanthe remainder of the body section 304. Metallic member of golf club head300 may generally be used to provide structural rigidity and a solidfeel to golf club head 300, and the composite members 310 are generallyused for weight saving purposes; however, it should be noted that theentire body section 304 may be made out of a composite member 310 toachieve the same objective of weight shifting without departing from thescope and content of the present invention. As indicated previously, inorder to create even more discretionary weight, more and more componentsof body section 304 may be replaced with composite member 310 withoutdeparting from the scope of the present invention. As shown in thecurrent exemplary embodiment in FIG. 3, composite member 310 may be usedto replace a crown section 306 of the golf club head 300 or in analternative embodiment, composite member 310 could also be used toreplace the sole section 308, the skirt section, a toe section, a heelsection, or any other sections of body section 304 all without departingfrom the scope of the present invention.

FIG. 3 also shows the composite member 310 filling in the area of golfclub head 300 that is not made out of the metallic material. Put inanother way, the composite member 310 fills in gaps in the external wallof golf club head 300 that is not made out of a metallic material.However, composite member 310 can also work in conjunction with metallicmember to form a dual layer golf club head 300 to contain an overlappingprofile that achieves the same sound tuning characteristic withoutdeparting from the scope of the present invention. Composite member 310,as shown in this current exemplary embodiment provides a majority of thesurface area of golf club head 300 via body section 304; howevercomposite member 310 may also be strategically placed at variouslocations of golf club head 300 without providing a majority of thesurface area of golf club head 300 without departing from the scope ofthe present invention.

Composite member 310 may be further comprised of a sandwiching outerlayer 312, a sandwiching inner layer 314, and a sandwiched core layer316. It should be noted that even though sandwiching outer layer 312 andthe sandwiching inner layer 314 are separated by a sandwiched core layer316, they may generally be made out of the same material; however,sandwiching outer layer 312 and sandwiching inner layer 314 may be madeout of different materials with different characteristic withoutdeparting from the scope of the present invention. Sandwiching outerlayer 312 and sandwiching inner layer 314 could be comprised of variousdifferent polymers such as plies of pre-preg material, thermoplasticmaterials such as polyurethanes, polyesters, polyamides, ionomers,continuous fiber pre-preg material, injection molded plastic, buckypaper, or any other similar material that has a lighter weight withoutdeparting from the scope of the present invention. Alternatively,sandwiching outer layer 312 and sandwiching inner layer 314 may also becomprised of metallic materials such as aluminum, titanium, magnesium,or any other metallic material that is lightweight without departingfrom the scope of the present invention. In a preferred embodiment, thesandwiching outer layer 312 and sandwiching inner layer 314 may be madeout of carbon fiber due to its high strength and weight savingqualities.

Sandwiched core layer 316, as shown in the current exemplary embodimentcontains a thickness profile that may bulge into the internal cavity ofgolf club head 300 to increase the area and volume of sandwiched corelayer 316, hence allowing an increase stiffness and vibration damping.However, it is worth noting that sandwiched core layer 316 may contain athickness profile that is uniform in thickness within the entire rangeof composite member 310, bulges out away from the external surface ofgolf club head 300, or any other thickness profile that is capable ofproviding structural stiffness and vibration damping without departingfrom the scope of the present invention.

Sandwiched core layer 316, as shown in the current exemplary embodimentmay generally be made out of various different materials ranging fromplastic polymer, aluminum polymer, foam, resin impregnated paper, balsawood, bucky paper, filled vinyl polymer, visco elastic polymer, rubber,or any type or material that is of a low density and has substantialcompressibility such that it can withstand the manufacturing processwithout collapsing all without departing from the scope of the presentinvention. Sandwiched core layer 316 could also be in various differentshapes such as a honeycomb hexagonal shape, trapezoidal shape,triangular shape, pyramidal shape, conic shape, cylindrical shape,spherical shape, rhombus shape, or any other shape that is capable ofproviding increased structural stiffness while minimizing density andweight of golf club head 300 all without departing from the scope of thepresent invention.

Sandwiched core layer 316, as shown in the current exemplary embodimentmay generally be comprised of a lightweight material to creatediscretionary weight; however, sandwiched core layer 316 may also be adense heavy material that allows specific weights to be placed atvarious locations of golf club head 300 without the need for alternativeattachment means without departing from the scope and content of thepresent invention.

It should also be noted here that although sandwiched core layer 316 mayoften be capable of adding structural stiffness, sandwiched core layer316 may also serve a purely vibration damping purpose that does notenhance structural stiffness without departing from the scope of thepresent invention. For example, sandwiched core layer 316 could also beof a foam type material, cotton type material, or any other materialcapable of absorbing vibration damping without adding structuralstiffness all without departing from the scope of the present invention.

The current invention may achieve improved sound characteristics byincreasing structural stiffness in two ways utilizing the compositemember 310. First, the separation of sandwiching outer layer 312 and thesandwiching inner layer 314 helps achieve increased structural inertia,which in turn increases the stiffness of the material. Because thestructural inertia of a composite material increases with the separationof the structural material, just by separating sandwiching outer layer312 from sandwiching inner layer 314 alone, the structural stiffness ofcomposite member 310 increases. Secondly, sandwiched core layer 316could also increase structural stiffness either through its physicalproperties or through geometric shapes such as a honeycomb mentionedabove. By interposing a sandwiched core layer 316 between sandwichingouter layer 312 and sandwiching inner layer 314, the composite member310 achieves significant improvement in structural stiffness in at leastthe two methods mentioned above.

FIG. 4 shows a side view of an alternative embodiment of a golf clubhead 400 in accordance with the present invention wherein the compositemember 410 is placed at the sole section 408 of golf club head 400. Thisalternative embodiment, as described above, may be used to providestructural stiffness at the sole section 408 or provide sound tuning atthe sole section 408 of the golf club head 400.

FIG. 5 shoes a cross-sectional view of the alternative embodiment of thepresent invention as shown in FIG. 4, wherein the composite member 510is placed at the sole section of golf club head 500. Similar to thecross sectional view presented in FIG. 3, the current alternativeembodiment shows a sandwiching outer layer 512, a sandwiching innerlayer 514, and a sandwiched core layer 516 interposed between thesandwiching outer layer 512 and a sandwiching inner layer 514. Theselayers may contain the same characteristics as those described in FIG.3, but placed at the sole section 508 also to achieve sound tuning andstiffening of golf club head 500.

FIG. 6 shows a cross-sectional view of a golf club head 600 inaccordance with a further alternative embodiment of the presentinvention wherein the composite member 610 may contain a sandwiched corelayer 616 with a uniform thickness profile interposed betweensandwiching outer layer 612 and sandwiching inner layer 614. It shouldbe noted that although FIG. 6 depicts this further alternativeembodiment to have the composite member 610 in the crown section 606,the composite member 610 may be placed at the sole section 608, theskirt section, the heel section, the toe section, or any other sectionwithin golf club head 600 all without departing from the scope of thepresent invention.

FIG. 7 shows a cross-sectional view of a golf club head 700 inaccordance with a further alternative embodiment of the presentinvention wherein the composite member 710 may contain a sandwiched corelayer 716 with thickness profile that bulges out away from golf clubhead 700, and interposed between sandwiching outer layer 712 andsandwiching inner layer 714. It should be noted that although FIG. 7depicts this further alternative embodiment to have the composite member710 in the crown section 706, the composite member 710 may be placed atthe sole section 708, the skirt section, the heel section, the toesection, or any other section within golf club head 700 all withoutdeparting from the scope of the present invention.

FIG. 8 shows a top view of a further alternative embodiment of thepresent invention wherein although the composite member 810 covers amajority of the crown section 806, the sandwiched core layer 816interposed inside the composite member 810 may only occupy a partialsection of composite member 810. Sandwiched core layer 816 may be placedin a way that strategically occupies a location that coincides with thevibration damping needs of a golf club head 800 upon impact with a golfball. Once again, it should be noted that although in FIG. 8, thecomposite member 810 is located in the crown section 806, the compositemember 810 may be placed at the sole section, the skirt section, theheel section, the toe section or any other section with golf club head800 all without departing from the scope of the present invention. Thesandwiched core layer 816 in this current exemplary embodiment may beplaced at the crown section 806 near the hosel of golf club head 800;however, sandwiched core layer 816 may also be placed toward the toesection, the leading edge, the trailing edge, on the crown, on the sole,on the skirt, or any other location on golf club head 800 that needsvibration damping all without departing from the scope of the presentinvention. Finally, although third section 816 may be square in shape inFIG. 8, third section 816 may be rectangular in shape, circular inshape, triangular shape, trapezoidal in shape, octagonal in shape,crisscross in shape, or any other shape that is capable of addressingthe vibration damping needs of golf club head 800 without departing fromthe scope of the present invention.

FIG. 9 shows a top view of a further alternative embodiment of thepresent invention wherein the sandwiched core layer 916 interposedinside the composite member 910 takes on a rectangular shape at adifferent location on golf club head 900. This alternative embodiment ofgolf club head 900 identifies another potential location within golfclub head 900 wherein vibration damping coincides with the soundimprovement needs of golf club head 900 when it comes in contact with agolf ball. Sandwiched core layer 916 may also be placed toward the toesection, the leading edge, the trailing edge, on the crown, on the sole,on the skirt, or any other location on golf club head 900 that needsvibration damping all without departing from the scope of the presentinvention.

FIG. 10 shows a top view of a further alternative embodiment of thepresent invention wherein the sandwiched core layer 1016 interposedinside the composite member 1010 takes on a circular shape at adifferent location on golf club head 1000. This alternative embodimentof golf club head 1000 identifies another potential location within golfclub head 1000 wherein vibration damping could be needed when golf clubhead 1000 comes in contact with a golf ball. Sandwiched core layer 1016may also be placed toward the toe section, the leading edge, thetrailing edge, on the crown, on the sole, on the skirt, or any otherlocation on golf club head 1000 that needs vibration damping all withoutdeparting from the scope of the present invention.

FIG. 11 shows a top view of a further alternative embodiment of thepresent invention wherein the sandwiched core layer 1116 interposedinside composite member 1110 takes on a multiple elongated rectangularshape at various different locations on golf club head 1100. Thisalternative embodiment of golf club head 1100 allows multiple sandwichedcore layers 1116 to be interposed inside composite member 1110 toprovide vibration damping at multiple locations within golf club head1100. Sandwiched core layer 1116 may also be placed toward the toesection, the leading edge, the trailing edge, on the crown, on the sole,on the skirt, or any other location on golf club head 1100 that needsvibration damping all without departing from the scope of the presentinvention.

FIG. 12 shows a cross-sectional view of a further embodiment of thepresent invention taken along the middle of golf club head 1100 asdepicted by line A-A′ in FIG. 11. Similar to golf club head 1100, golfclub head 1200 has multiple sandwiched core layers 1216 interposedinside composite member 1210, between sandwiching outer layer 1212 andsandwiching inner layer 1214. FIG. 12 demonstrates that the sandwichedcore layers 1216 protrude into the cavity of the golf club head 1200;however, as illustrated above, sandwiched core layers 1216 may have auniform thickness within composite member 1210, or even protrude out ofgolf club head 1200 all without departing from the scope of the presentinvention. Finally, although sandwiched core layers 1216 in this currentexemplary embodiment may be shown as a uniform material, sandwiched corelayers 1216 may be comprised of dual materials, or even multiplematerials to address the various strengthening and vibration dampeningneeds of sandwiched core layers 1216 all without departing from thescope of the present invention.

FIG. 13 shows a top view of a further alternative embodiment of a golfclub head 1305, including a hosel 1315, wherein the sandwiched corelayer 1335 comprises voids 1345. As shown in FIG. 13, the sandwichedcore layer may be arranged to create a patterned material, e.g.,including voids 1345, e.g., creating a honeycomb structure. Otherpatterns are contemplated, as discussed below with respect to FIG. 15.The sandwiched core layer 1335 may be constructed from lightweightmaterials, such as foam, resin-impregnated paper, a plastic polymer,balsa wood, visco-elastic polymers, rubber, and cotton. In someembodiments, the sandwiched core layer 1335 may be constructed frommetals such as aluminum, titanium, or magnesium. The sandwiched corelayer 1335 is interposed between outer sandwich layer 1325 and innersandwich layer 1355. As shown in FIG. 13, the outer sandwich layer maybe a transparent material, such as a transparent composite material,e.g., a transparent resin. Accordingly, the embodiment of FIG. 13 allowsa user to see the inner structure of the sandwiched core layer 1335. Theconstruction is not limited to this arrangement, however, as the outersandwich layer 1325 may be transparent, translucent, or opaque.

The outer sandwich layer 1325 may be constructed from metals, such astitanium, aluminum, magnesium, or steel. The outer sandwich 1325 layermay be constructed from composites, including carbon fiber, polymers, orpolymers including reinforcing fibers. The inner sandwich layer 1355 maybe constructed from metals, such as titanium, aluminum, magnesium, orsteel. The inner sandwich layer 1355 may be constructed from composites,including carbon fiber, polymers, or polymers including reinforcingfibers. The embodiment of a golf club head shown in FIG. 13 also allowsmultiple sandwiched core layers 1335 to be interposed between outersandwich layer 1325 and inner sandwich layer 1355.

FIG. 14 shows a cross-sectional view of the embodiment of FIG. 13 takenalong the middle of golf club head 1305 as depicted by line B-B′ in FIG.13. Similar to other golf club heads of the invention, golf club head1305 has a sandwiched core layer 1335 interposed between outer sandwichlayer 1325 and inner sandwich layer 1355. FIG. 14 demonstrates that thesandwiched core layer 1335 protrudes into the cavity of the golf clubhead 1305; however, as discussed previously, sandwiched core layer 1335may have a uniform thickness between outer sandwich layer 1325 and innersandwich layer 1355, or even protrude out of golf club head 1305 allwithout departing from the scope of the present invention. Finally,although sandwiched core layer 1335 in this embodiment may be shown as auniform material, sandwiched core layer 1335 may be comprised of dualmaterials, or even multiple materials to address the variousstrengthening and vibration dampening needs of sandwiched core layer1335 all without departing from the scope of the present invention.

FIG. 15 shows a top view of a further alternative embodiment of a golfclub head 1505, including a hosel 1515, wherein the sandwiched corelayer 1535 comprises voids 1545. As shown in FIG. 15, the sandwichedcore layer may be arranged to create a patterned material, e.g.,including voids 1545, e.g., creating a cellular structure. A cellularstructure may include any biologically-inspired distribution ofmaterial, such as found, for example, in the cell wall structure of awoody material, the reinforcing fibers of a leaf, or the supportstructures within an insect wing, such as a dragonfly wing. A cellularpattern, such as shown in FIG. 15, differs from the regular pattern of,for example, a honeycomb as shown in FIG. 13, because the voids are notall of a uniform size. Because the voids are not uniform in size, itallows for greater structural strength (i.e., more cells) in the areaswhere the strength is needed, but less structural strength (i.e., fewercells) in the areas where the strength is not needed, while using thesame amount of material (and the same weight) as a regular pattern, suchas a honeycomb. The sandwiched core layer 1535 may be constructed fromlightweight materials, such as foam, resin-impregnated paper, a plasticpolymer, balsa wood, visco-elastic polymers, rubber, and cotton. In someembodiments, the sandwiched core layer 1535 may be constructed frommetals such as aluminum, titanium, or magnesium. The sandwiched corelayer 1535 is interposed between outer sandwich layer 1525 and innersandwich layer 1555. As shown in FIG. 15, the outer sandwich layer maybe a transparent material, such as a transparent composite material,e.g., a transparent resin. Accordingly, the embodiment of FIG. 15 allowsa user to see the inner structure of the sandwiched core layer 1535. Theconstruction is not limited to this arrangement, however, as the outersandwich layer 1525 may be transparent, translucent, or opaque.

The outer sandwich layer 1525 may be constructed from metals, such astitanium, aluminum, magnesium, or steel. The outer sandwich 1525 layermay be constructed from composites, including carbon fiber, polymers, orpolymers including reinforcing fibers. The inner sandwich layer 1555 maybe constructed from metals, such as titanium, aluminum, magnesium, orsteel. The inner sandwich layer 1555 may be constructed from composites,including carbon fiber, polymers, or polymers including reinforcingfibers. The embodiment of a golf club head shown in FIG. 15 also allowsmultiple sandwiched core layers 1535 to be interposed between outersandwich layer 1525 and inner sandwich layer 1555.

FIG. 16 shows a cross-sectional view of the embodiment of FIG. 15 takenalong the middle of golf club head 1505 as depicted by line C-C′ in FIG.15. Similar to other golf club heads of the invention, golf club head1505 has a sandwiched core layer 1535 interposed between outer sandwichlayer 1525 and inner sandwich layer 1555. FIG. 16 demonstrates that thesandwiched core layer 1535 protrudes into the cavity of the golf clubhead 1505; however, as discussed previously, sandwiched core layer 1535may have a uniform thickness between outer sandwich layer 1525 and innersandwich layer 1555, or even protrude out of golf club head 1505 allwithout departing from the scope of the present invention. Finally,although sandwiched core layer 1535 in this embodiment may be shown as auniform material, sandwiched core layer 1535 may be comprised of dualmaterials, or even multiple materials to address the variousstrengthening and vibration dampening needs of sandwiched core layer1535 all without departing from the scope of the present invention.

As shown in the aforementioned various figures, a preferred embodimentof the present invention utilizes structural stiffness and vibrationdamping to control the sound characteristics of a golf club head when itcomes in contact with a golf ball. Given a golf club swing speed ofapproximately 80 miles per hour (“MPH”) to approximately 130 MPH, a golfclub head could potentially reach amplitude of 125 decibels (“dB”) whenmeasured at a distance of 1 foot. However, a golf club in accordancewith the present invention, given the same swing speed, may yield anamplitude level less than approximately 125 dB, preferably of anamplitude level of less than approximately 120 dB, and even morepreferably an amplitude level of less than approximately 110 dB, andmore preferably an amplitude level of less than approximately 100 dB.

Although amplitude is an important characteristic of sound, a preferredembodiment of the present invention that utilizes structural stiffnessand vibration damping will also be able to control the frequency of agolf club head when it comes in contact with a golf ball. Given a golfclub swing speed of approximately 80 MPH to approximately 130 MPH, agolf club head in accordance with the present invention may yield afrequency greater than approximately 2500 hertz (“Hz”), preferably of afrequency greater than approximately 3000 Hz, and more preferablygreater than approximately 3500 Hz. A further discussion of thefrequency values associated with reduction in noise can also be found inU.S. Pat. No. 7,297,072, the disclosure of which is incorporated byreference in its entirety.

It should be understood, of course, that the foregoing relates toexemplary embodiments of the invention and that modifications may bemade without departing from the scope and content of the invention asset forth in the following claims.

1. A golf club head comprising: a hitting face providing a surface forstriking a golf ball; a body section including a crown section and asole section, the body section extending from said hitting face, thehitting face, crown section, and sole sections forming an interiorcavity of the club head, the crown section comprising a sandwichingouter layer, a sandwiching inner layer, and a sandwiched core layer. 2.The golf club head of claim 1, wherein the sandwiching outer layer orthe sandwiching inner layer comprises titanium, aluminum, or a compositematerial.
 3. The golf club head of claim 2, wherein the sandwichingouter layer or the sandwiching inner layer comprises titanium.
 4. Thegolf club head of claim 2, wherein the sandwiching outer layer or thesandwiching inner layer comprises a composite material.
 5. The golf clubhead of claim 4, wherein the composite material comprises carbon fiber.6. The golf club head of claim 1, wherein the sandwiched core layercomprises foam, resin-impregnated paper, a plastic polymer, balsa wood,a visco-elastic polymer, rubber, and cotton.
 7. The golf club head ofclaim 1, wherein the sandwiched core layer comprises voids.
 8. The golfclub head of claim 7, wherein the voids form a honeycomb pattern.
 9. Thegolf club head of claim 7, wherein the voids form a cellular pattern.10. The golf club head of claim 7, wherein the sandwiching outer layercomprises titanium and the sandwiching inner layer comprises acomposite.
 11. The golf club head of claim 7, wherein the sandwichingouter layer comprises a composite and the sandwiching inner layercomprises titanium.
 12. A hollow golf head comprising a face, a sole,and a crown, the crown including a sandwiched core layer interposedbetween layers of material.
 13. The golf club head of claim 12, whereinthe layers of material comprise titanium, aluminum, or a compositematerial.
 14. The golf club head of claim 13, wherein at least one ofthe layers comprises titanium.
 15. The golf club head of claim 13,wherein at least one of the layers comprises a composite material. 16.The golf club head of claim 15, wherein the composite material comprisescarbon fiber.
 17. The golf club head of claim 12, wherein the sandwichedcore layer comprises foam, resin-impregnated paper, a plastic polymer,balsa wood, a visco-elastic polymer, rubber, and cotton.
 18. The golfclub head of claim 12, wherein the sandwiched core layer comprisesvoids.
 19. The golf club head of claim 18, wherein the voids form ahoneycomb pattern.
 20. The golf club head of claim 18, wherein the voidsform a cellular pattern.